The article, entitled Intense Optical Activity from Three-Dimensional Chiral Ordering of Plasmonic Nanoantennas (2011, 50, 24, 5499-5503), presents experimental evidence of surface-plasmon-mediated circular dichroism (SP-CD), the result of chiral 3D organizations of gold nanorods on a helical gel fiber template. The CD signal occurs at a wavelength of the longitudinal surface-plasmon resonance of nanorods. Under the same experimental conditions, nanospheres do not exhibit optical activity. It has been demonstrated that the SP-CD effect depends upon the stereochemical configuration of the gelator, which determines the P or M helicity of the fiber (figure on the right). In this manner, the chirality of the template is transferred to the nano-particles. Numerical simulations based on a coupled dipole model confirm the crucial role of gold nanorods for the occurrence of such intense circular dichroism.

Successful collaboration is ongoing between the Laboratory for Supramolecular and Nucleoside Chemistry and the research group led by Prof. Luis M. Liz-Marzán and Dr. Andrés Guerrero-Martínez of Departamento de Quimica Fisica and Unidad Asociada CSIC, Universidade de Vigo.